Touch panels are used as input devices for a variety of host appliances and systems such as automated teller machines (ATMs), automobiles, computers, tablets, home security systems, etc. It is sometimes possible for a second, phony, input device to communicate with a host. Identification codes may be used to authenticate and reject such phony input devices. The input device provides the identification code and the host compares it to a stored identifier (ID). If the provided ID does not match the stored ID then the host may reject commands or data provided by the input device. It is possible, however, to acquire device IDs that are stored in a memory at a legitimate input device, for example, by cloning, enabling a phony device to provide the ID to the host.